Faust, Royal Opera House London

If you knew that Gounod's Faust was showing up at the Royal Opera for the first time in 18 years, and that the leading roles were going to be another on-stage love affair between the public's favourite husband- and-wife duo, Roberto Alagna and Angela Gheorghiu, you'd be ready for a safe, deferential production, to hold them like a crown bearing jewels.

If you knew that Gounod's Faust was showing up at the Royal Opera for the first time in 18 years, and that the leading roles were going to be another on-stage love affair between the public's favourite husband- and-wife duo, Roberto Alagna and Angela Gheorghiu, you'd be ready for a safe, deferential production, to hold them like a crown bearing jewels.

If you then heard that the night's sensation was the ballet in Act V, you'd think the reporter mad. But it happened. The superstar couple sang their hearts out and even acted passably, but they took their place, along with the howling, biting, sword-swinging, sexually aggressive dancers as two of the strengths in David McVicar's spectacular reinvention of this 19th-century warhorse with a dodgy reputation.

Surprisingly for such a popular and successful work, this was only the company's second production since 1938. But the public appetite for it has lasted, and no wonder. The second and third acts present a dazzling sequence of well-characterised arias. One for every principal and two in succession for the heroine, followed by a love duet.

Among the most stylish performances was that of Simon Keenlyside as Valentin, an ungrateful role with a mean spirit, but before that emerges, a suave and stirring aria that he sang with aplomb. Bryn Terfel, in a bewildering succession of suits, gave Mephistopheles a believable domineering menace without compromising the splendour of the voice. Sophie Koch made a fetching moment of Siebel's exquisite number.

And then the two big draws: Alagna pushing uncomfortably hard at first, but achieving a kind of elegance as well as energy; Gheorghiu eloquent and fluent from the start, the "Jewel Song" supple and eager rather than flashy.

McVicar's rethink started by moving the action to Second Empire Paris - the milieu of the opera's rise to fame, which added a gleeful, knowing layer of period commentary. The waltz was danced like a cancan in Hell's Cabaret. Faust couldn't get on to Marguerite's balcony, so Mephistopheles wheeled on a mock-Gothic staircase for him. Designs by Charles Edwards and Brigitte Reiffenstuel went to town on quotes from French paintings, and alternated between street scenes and interiors, the latter making an exuberant pun between a cathedral and the Paris Opéra.

Then, in the later acts, the vision turned dark. The seamy underbelly of glitzy Paris emerged as the Devil took over Faust's soul. And there was that ballet. Faust, successively degraded, was now injecting drugs. An episode that is usually slightly ridiculous turned into a nightmare vision of, perhaps, what the ballet girls really had to do for the ogling gentlemen. Tricky, yes, but a searing 10 minutes that haunts the imagination long after.

To 2 July (020-7304 4000)